Process of recovering soluble compounds of potassium and aluminum from silicates



Patented July 31, 1923.

lint-rel) STATES PATENT OFFICE.

PROCESS OFJEECOVERING SOLUBLE COMPOUNDS F POTASSIUM AND ALUMINUM FROM SILICATES.

In Drawing.

To all whom it may concern:

Be it known that I. Bmonn Emu) Harmon- SEN, a subject of the King of Norway. residing at Christianiu. in the Kingdom of Norway. have invented certain nqlv and useful Improvements in a Process of Recoverin Soluble Ct .npounds of Potassium and A uminum from Silicates (for which I have obtained patents in Norway, No. 27883, application filed May th. 1916; Sweden. No. 47044. application filed May29. 1917; Switzerland, No. 77376. application filed May 2( 1917; France. No. 436.577. application tiled June 6. 1917: Italy, application No.247/773, l5 filed May 29. 1917; Spain, No. 64710. application filed June 8. 1917: t'anada. No. 186,-

421. application filed June 7. 1917; Great Britain. No. 107.012. application filed May 30. 1917); and he does hereby declare the following to be a full. clear. and exact description of the invention, such as will enable others skilled in the art to which it, appertains to make and use the same.

This invention has for its object a process of recovering soluble compounds of potassium and aluminum from silicates.

According to the present invention the decomposition by means of calcium cyanamidc is carried into effect in a special manner characterized by the combination of the decomposition operation with the process of converting the nitrogen of the cyanamide into ammonia.

This conversion of the cyanamide into ammonia is usually carried into effect. on an in,-

dustrial scale by means of heating the cyanamide in autoclavcs in the presence of water; It is also known that it is possible instead of water in autoclaves to use superheated steam at higher temperatures for instance 650 C. and more. It has been found that when alkali-metal aluminum silicate (fels at) in a finely divided condition are addeg to the cyanamide of calcium previ- 1 Application filed March 26, 1921. Serial No. 455 ,823.

ously to the decomposition operation the alkali and the alumina are in part converted into soluble form. \Vhat isactually taking place is as will be seen a decomposition by means of lime or carbonate of calcium.

It has also been found that the reaction is facilitated by the addition of salts such as chlorides. nitrates. sulphates, etc.

1 claim:

'1. The process which consists in heating a mixture of'alkali-metal aluminum silicates and cyanamidc of calcium in the presence of water.

2. The process which consists in heating a mixture of alkali-metal aluminum silicates and cyanamide tit-calcium in the presence of water inthe form of superheated steam.

3. The process which consists in heating a mixture of alkali-metal aluminum silicates and cyanamide of calcium in the presence of water in the form of'si iperheated steam at temperatures above 650 (h 4. The process which consists in heating a mixture of alkali-metal aluminum silicates and cyanamidc of calcium in theprcsence of water under pressure in a closcdycssel and at a temperature above 11W j 5. The process which consists in heating miniature of alkali-metal aluminuiirsilieates and cyanamidc of calcium in the prescnccol' water and |'(('0\'01|II; the resulting soh ljlo:

BIRGER FJELI) HALVORSEN. Witnesses:

C. NORMAN.

KARL L. LED. 

